JP2005309440A - Plasma display device and its driving method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plasma display device with which luminance is increased while energy efficiency is increased and a sustain voltage is adjusted in accordance with the amount of load and to provide its driving method. <P>SOLUTION: The plasma display device includes a scan driving section having a sustain driving circuit, which makes it possible to include a picking pulse in one sustain pulse so that a plurality of discharges are generated by one sustain pulse when the sustain pulse is supplied to a plasma panel and a prescribed electrode of the plasma panel, and a sustain driving section. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a plasma display device and a driving method thereof.

  In general, a plasma display panel (Plasma DiSplaY Panel: hereinafter referred to as “PDP”) emits phosphors by emitting light of 147 nm ultraviolet rays generated when He + Xe or Ne + Xe inert gas mixture is discharged. Display an image containing graphics.

  FIG. 1 is a perspective view showing a structure of a three-electrode AC surface discharge type PDP having a discharge cell structure arranged in a conventional matrix form. Referring to FIG. 1, the three-electrode AC surface discharge type PDP 100 includes a scan electrode 11 a and a sustain electrode 12 a formed on the upper substrate 10, and an address electrode 22 formed on the lower substrate 20. Each of the scan electrode 11a and the sustain electrode 12a is formed of a transparent electrode, for example, indium tin oxide (ITO). Metal bus electrodes (11b, 12b) for reducing resistance are formed on the scan electrode 11a and the sustain electrode 12a, respectively. An upper dielectric layer 13a and a protective film 14 are stacked on the upper substrate 10 on which the scan electrode 11a and the sustain electrode 12a are formed. Wall charges generated during the plasma discharge are accumulated in the upper dielectric layer 13a. The protective film 14 increases the secondary electron emission efficiency while preventing the upper dielectric layer 13a from being damaged by sputtering generated during plasma discharge. The protective film 14 is usually made of magnesium oxide (MgO).

  On the other hand, a lower dielectric layer 13b and barrier ribs 21 are formed on the lower substrate 20 on which the address electrodes 22 are formed, and a phosphor layer 23 is applied to the surfaces of the lower dielectric layer 13b and barrier ribs 21. . The address electrode 22 is formed in a direction intersecting with the scan electrode 11a and the sustain electrode 12a. The barrier ribs 21 are formed side by side with the address electrodes 22 and prevent ultraviolet rays and visible light generated by discharge from leaking to the discharge cells in contact therewith. The phosphor layer 23 is excited by ultraviolet rays generated at the time of plasma discharge to generate any one visible light of red (R), green (G), and blue (B). An inert mixed gas such as He + Xe or Ne + Xe for discharge is injected into the discharge space of the discharge cell defined by the barrier ribs 21 between the upper substrate 10 and the lower substrate 20. A driving method of the conventional PDP having such a structure is shown in FIG.

  FIG. 2 is a drive waveform for explaining a conventional PDP drive method. 2, a conventional PDP is driven by being divided into a reset period for initializing the entire screen, an address period for selecting a cell, and a sustain period for maintaining discharge of the selected cell. .

  First, although the reset period is driven by being divided into a setup period (SU) and a set-down period (SD), the rising ramp waveform (Ramp-up) is applied to all the scan electrodes (Y) in the setup period (SU). Are applied simultaneously. This rising ramp waveform causes a discharge in the cells of the full screen. By this setup discharge, positive wall charges are accumulated on the address electrode (X) and the sustain electrode (Z), and negative wall charges are accumulated on the scan electrode (Y). In the set-down period (SD), after the rising ramp waveform is supplied, the falling ramp waveform starts to drop from the positive voltage lower than the peak voltage of the rising ramp waveform and falls to the base voltage (GND) or the specific voltage level of negative polarity ( Ramp-down) causes a weak erasing discharge in the cell and partially erases excessively formed wall charges. This set-down discharge leaves wall charges uniformly in the cell so that address discharge can occur stably.

  In the address period, a negative scan pulse (Scan) is sequentially applied to the scan electrode (Y), and at the same time, a positive data pulse (data) is applied to the address electrode (X) in synchronization with the scan pulse. The While the voltage difference between the scan pulse and the data pulse and the wall voltage generated in the reset period are added, an address discharge is generated in the cell to which the data pulse is applied. In the cell selected by the address discharge, a wall charge is formed so that the discharge can occur when the sustain voltage is applied. The sustain electrode (Z) has a positive direct current voltage (Zdc) so as to reduce a voltage difference from the scan electrode (Y) between the set-down period and the address period so that no erroneous discharge occurs with the scan electrode (Y). Is supplied.

  During the sustain period, a sustain pulse (sus) is alternately applied to the scan electrode (Y) and the sustain electrode (Z). In the cell selected by the address discharge, a sustain discharge, that is, a display discharge occurs between the scan electrode (Y) and the sustain electrode (Z) every time the sustain pulse is applied while the cell inner wall voltage and the sustain pulse are applied. It becomes like this. In addition, after the sustain discharge is completed, a ramp waveform (Ramp-ers) having a small pulse width and voltage level is supplied to the sustain electrode (Z) to erase wall charges remaining in the cells of the entire screen.

  On the other hand, FIGS. 3 and 4 show a waveform diagram of a sustain pulse applied to the scan electrode or the sustain electrode during the sustain period described above, and a sustain drive circuit for generating the sustain pulse.

  FIG. 3 is a conventional general sustain drive circuit diagram, and FIG. 4 is a general sustain pulse waveform diagram.

  Referring to FIGS. 3 and 4, first, the first switch (Q1) and the fourth switch (Q4) are turned on, and the second switch (Q2) and the third switch (Q3) are turned off. As a result, the voltage source Vs is applied to the Y electrode, the voltage of Vy becomes Vs, the Z electrode becomes the ground level, and VZ becomes 0V. At this time, the current supplied from the voltage source Vs flows through the first switching (Q1), the panel (C), and the fourth switch (Q4).

Next, the third switch (Q3) and the second switch (Q3) are turned on, and the first switch (Q1) and the fourth switch (Q4) are turned off. As a result, the charge charged in the panel (C) is discharged through the second switch (Q2), the voltage source Vs is applied to the Z electrode, the voltage of Vz becomes Vs, and the Y electrode becomes the ground level. Vy becomes 0V. The current supplied from the voltage source Vs flows through the third switching (Q3), the panel (C), and the second switch (Q2).
In such a conventional driving device and driving method, since the electric charge injected from the voltage source Vs is discharged to the ground through the second switch (Q2) or the fourth switch (Q4) during the operation of the driving device, the energy efficiency is very high. Not good. Therefore, if the conventional driving device tries to increase the luminance, more energy must be used, and thus the energy efficiency becomes worse.

  On the other hand, a conventional PDP image gradation expression method is shown in FIG.

  FIG. 5 is a diagram illustrating a method for realizing image gradation of a conventional plasma display panel.

  As shown in FIG. 5, in the conventional plasma display panel, the gray level is divided into a plurality of subfields with different numbers of times of light emission, and each subfield also initializes all cells. A reset period (RPD), an address period (APD) for selecting a cell to be discharged, and a sustain period (SPD) for implementing gray levels according to the number of discharges. For example, when an image is to be displayed with 256 gradations, a frame period (16.67 ms) corresponding to 1/60 seconds is divided into 8 subfields (SF1 to SF8) as shown in FIG. Each of the subfields (SF1 to SF8) is divided into a reset period, an address period, and a sustain period.

The reset period and address period of each subfield are equal for each subfield. Address discharge for selecting a cell to be discharged is caused by a voltage difference between the address electrode and the transparent electrode which is a scan electrode. The sustain period is increased at a rate of 2 ^{n in} each subfield (where n = 0, 1, 2, 3, 4, 5, 6, 7). As described above, since the sustain period changes in each subfield, the gradation of the image is expressed by adjusting the sustain period of each subfield, that is, the number of sustain discharges.

  As described above, each gradation is represented by a combination of the subfields, and the number of sustain pulses assigned to each subfield varies depending on the weight of the subfield.

  At this time, the voltage drop amount of the sustain voltage increases as the load increases in proportion to the number of cells turned on. That is, assuming that the sustain voltage is 100V, the voltage applied to the scan electrode (Y) and the sustain electrode (Z) is a voltage lower than 100V due to the voltage drop, and the voltage drop increases as the load increases. Become. Even if the number of sustain pulses is increased in order to compensate for the decreased brightness even though the brightness is decreased, the voltage drop amount per sustain pulse is constant because the magnitude of the sustain voltage is constant. There is a problem in that the luminance to be compensated decreases as the number of the power increases as compared with the power consumed.

  An object of the present invention is to provide a plasma display apparatus and a driving method thereof that can increase the luminance while increasing the energy efficiency, and can adjust the magnitude of the sustain voltage according to the load amount.

  In addition, the present invention provides a plasma display panel driving apparatus and a driving method thereof that can increase the luminance and contrast by forming a peaking pulse as well as adjusting the magnitude of the sustain voltage according to the load amount. It provides.

  In the plasma display apparatus according to the present invention, when a sustain pulse is supplied to a plasma display panel and a predetermined electrode of the plasma display panel, a picking pulse is generated in the one sustain pulse so that a plurality of discharges are generated by the one sustain pulse. A scan driving unit and a sustain driving unit including a sustain driving circuit to be included are included.

  The driving method of the plasma display apparatus according to the present invention includes converting the input video signal to match the plasma display panel to form the rearranged video data for each subfield; Receiving the received video data and measuring a load amount; comparing the measured load amount with a reference load amount; outputting a voltage adjustment signal; determining a sustain voltage corresponding to the sustain voltage adjustment signal and determining the plasma display panel And applying to the scan electrode or the sustain electrode.

  The predetermined electrode of the plasma display panel may be at least one of a scan electrode and a sustain electrode.

  The sustain driving circuit includes a peaking pulse applying unit including a peaking pulse switch that is turned on when supplying energy from the energy storage unit to the plasma display panel, a peaking pulse applying unit including a diode for injecting energy into the energy storage unit, and the energy storage unit. A resonance part that forms a peaking pulse by LC resonance using energy and applies it to a scan electrode or a sustain electrode, and a sustain voltage control part that applies a sustain voltage to the scan electrode or the sustain electrode or maintains a ground level It is characterized by including.

  The peaking pulse is applied to the scan electrode or the sustain electrode before a sustain voltage is applied.

  The gate end of the peaking pulse switch receives a timing signal, the drain end is connected to the energy storage unit, the source end is connected to the anode end of the diode, and the diode end is connected to the peaking pulse switch. And the end of the anode is connected to the source end of the peaking pulse switch.

  The peaking pulse voltage is larger than the sustain voltage.

  The resonance unit includes a coil, wherein one end of the coil is connected to a source end of the peaking pulse switching element, and the other end is connected to the scan electrode or a sustain electrode.

  A load measurement unit that measures the load amount of video data converted in conformity with the plasma display panel, compares the measured load amount with a reference load amount, and outputs a voltage adjustment signal, and outputs from the load measurement unit And a voltage adjusting unit configured to adjust a sustain voltage according to the voltage adjustment signal and apply the sustain voltage to the scan electrode or the sustain electrode of the plasma display panel.

  The voltage adjusting unit supplies a voltage higher than the sustain reference voltage to the scan electrode or the sustain electrode of the plasma display panel when the measured load amount is larger than the reference load amount.

  When the measured load amount is larger than a reference load amount, the sustain pulse adjustment unit further includes a sustain pulse adjustment unit that receives a sustain pulse adjustment signal from the load measurement unit and adjusts the number of already assigned sustain pulses. The control unit controls the scan driving unit and the sustain driving unit to apply a sum of the reference sustain voltage and the increase value of the sustain voltage to the scan electrode or the sustain electrode when a sustain pulse is supplied. .

  The voltage adjusting unit applies the reference sustain voltage to the scan electrode or the sustain electrode when the measured load amount is smaller than the reference load amount.

  The voltage adjusting unit includes a DC / DC converter, and the DC / DC converter determines a rising value of the sustain voltage according to a pulse width of the sustain voltage adjusting signal.

  The driving method of the plasma display apparatus according to the present invention includes a step of converting an input video signal so as to hit the plasma display panel to form rearranged video data for each subfield, and a rearrangement for each subfield from the controller unit. Receiving the received video data and measuring the load amount; comparing the measured load amount with a reference load amount; outputting a voltage adjustment signal; and determining a sustain voltage corresponding to the sustain voltage adjustment signal to determine the plasma display The method includes applying to a scan electrode or a sustain electrode of the panel.

  When the measured load amount is larger than the reference load amount, the number of already assigned sustain pulses is adjusted.

  The method may further include applying the reference sustain voltage to the scan electrode or the sustain electrode when the measured load amount is smaller than the reference load amount.

  In the step of determining a sustain voltage corresponding to the sustain voltage adjustment signal and applying the sustain voltage to the scan electrode or the sustain electrode of the plasma display panel, a peaking pulse formed by LC resonance is applied to the scan electrode while injecting previously stored energy. A sustain voltage is applied to the scan electrode after the peaking pulse is applied and the sustain electrode becomes a ground level, and a peaking pulse formed by LC resonance is injected while energy stored in advance is injected. The method includes a step of applying a sustain voltage to the sustain electrode, and a step of applying a sustain voltage to the sustain electrode after the peaking pulse is applied to bring the scan electrode to a ground level.

  The sustain voltage is applied when the peaking pulse voltage reaches a maximum value.

  The peaking pulse voltage is larger than the sustain voltage.

  A discharge is generated by the peaking pulse.

  In the present invention, the sustain voltage is adjusted according to the load amount of the video data to advance the brightness and contrast characteristics, and at the same time, the peaking pulse is applied together with the sustain pulse at the LC resonance to save energy consumption. There is an effect that can improve efficiency.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 6 is a diagram schematically illustrating the plasma display apparatus according to the first embodiment of the present invention.

  As shown in FIG. 6, the first plasma display apparatus according to the present invention supplies data to the plasma display panel 100 and address electrodes (X1 to Xm) formed on a lower substrate (not shown) of the plasma display panel 100. A data driver 122 for driving, a scan driver 123 for driving the scan electrodes Y1 to Yn, a sustain driver 124 for driving the sustain electrode Z that is a common electrode, and a plasma display panel drive At this time, the timing controller 121 for controlling the data driver 122, the scan driver 123, and the sustain driver 124, and the driving voltage for supplying the necessary driving voltages to the respective drivers (122, 123, 124). Generator 125.

  The plasma display panel 100 is configured by attaching an upper substrate (not shown) and a lower substrate (not shown) at a predetermined interval. A plurality of electrodes, for example, scan electrodes (Y1 to Yn) and a sustain electrode (Z) are formed in pairs on the upper substrate. Address electrodes (X1 to Xm) are formed on the lower substrate so as to intersect the scan electrodes (Y1 to Yn) and the sustain electrode (Z).

  The data driver 122 is supplied with the data mapped to each subfield by the subfield mapping circuit after the inverse gamma correction and error diffusion by an unillustrated reverse gamma correction circuit, error diffusion circuit, or the like. The data driver 122 samples and latches data in response to the timing control signal (CTRX) from the timing controller 121, and then supplies the data to the address electrodes (X1 to Xm). .

  The scan driver 123 supplies the rising ramp waveform (Ramp-up) and the falling ramp waveform (Ramp-down) to the scan electrodes (Y1 to Yn) during the reset period under the control of the timing control unit 121. Further, the scan driver 123 sequentially supplies a scan pulse (Sp) of the scan voltage (−Vy) to the scan electrodes (Y1 to Yn) during the address period under the control of the timing controller 121, and during the sustain period. A sustain pulse generated by a sustain drive circuit provided inside is supplied to the scan electrode. At this time, one sustain pulse includes a picking pulse, and a plurality of discharges occur.

  The sustain driver 124 supplies a bias voltage of the sustain voltage (Vs) to the sustain electrode (Z) during the period when the falling ramp waveform (Ramp-down) is generated under the control of the timing controller 121 and the address period. . During the sustain period, the sustain driving circuit provided in the sustain driving unit 124 operates alternately with the sustain driving circuit provided in the scan driving unit 123 to apply the sustain pulse (sus) to the sustain electrode (Z). Supply. At this time, one sustain pulse includes a picking pulse and generates a plurality of discharges.

  On the other hand, as described above, all the sustain pulses generated by the sustain drive circuit included in the scan drive unit and the sustain drive unit include the picking pulse, so that the scan electrodes and the sustain electrodes can be supplied. However, in some cases, the scan electrode can be supplied only to the scan electrode or only to the sustain electrode, and the picking pulse is included in only some of the sustain pulses generated by the sustain driving circuit instead of the sustain pulse. It can be supplied to an electrode or a sustain electrode.

  The timing control unit 121 receives the vertical / horizontal synchronization signal and the clock signal, and controls the operation timing and synchronization of each driving unit (122, 123, 124) in the reset period, address period, and sustain period. By generating timing control signals (CTRX, CTRY, CTRZ) and supplying the timing control signals (CTRX, CTRY, CTRZ) to the corresponding driving units (122, 123, 124), each driving unit (122, 123, 124).

  On the other hand, the data control signal (CTRX) includes a sampling clock for sampling data, a latch control signal, and a switch control signal for controlling on / off times of the sustain drive circuit and the drive switch element. The scan control signal (CTRY) includes a switch control signal for controlling the on / off time of the sustain drive circuit and the drive switch element in the scan drive unit 123. The sustain control signal (CTRZ) includes a switch control signal for controlling the on / off time of the sustain drive circuit and the drive switch element in the sustain drive unit 124.

  The drive voltage generator 125 generates a setup voltage (Vsetup), a scan common voltage (Vscan-com), a scan voltage (−Vy), a sustain voltage (Vs), a data voltage (Vd), and the like. Such a driving voltage can vary depending on the formation of the discharge gas and the discharge cell structure.

  The plasma display apparatus having such a structure is as shown in FIGS. 7 and 8 when the sustain driving circuit included in the scan driving unit and the sustain driving unit and the waveform of the sustain pulse generated by the operation of the sustain driving circuit are seen. It is.

  FIG. 7 shows a sustain driving circuit included in the scan driving unit and the sustain driving unit of the present invention. FIG. 8 is a pulse waveform diagram generated by the operation of the sustain drive circuit of the present invention.

  First, referring to FIG. 7, a sustain driving circuit included in a scan driving unit (not shown) includes a first energy storage unit 310, a first peaking pulse application unit 315, a first resonance unit 320, a first resonance unit 320, and a first resonance unit 320. A sustain voltage controller 325 is included. The sustain driving circuit included in the sustain driving unit (not shown) includes a second energy storage unit 330, a second peaking pulse applying unit 335, a second resonance unit 340, and a second sustain voltage control unit 345.

  <First energy storage unit>

  The first energy storage unit 310 includes a capacitor Cs1 that stores energy necessary to apply a peaking pulse higher than the sustain voltage Vs to the scan electrode.

  <First peaking pulse application section>

  The first peaking pulse applying unit 315 includes a first peaking pulse switch (Qp1) and a first peaking pulse switch (Qp1) that are turned on when the energy supplied from the first energy storage unit 310 is supplied to the panel. A first diode (D1) connected in parallel to inject energy into the first energy storage unit 310;

  At this time, the first peaking pulse switch (Qp1) is a MOS FET, the gate end of the MOS FET accepts an input of a timing signal, and the drain end of the MOS FET is connected to the first energy storage unit 310. The cathode end of the first diode (D1) is connected to the drain end of the switch (Qp1), and the anode end of the first diode (D1) is connected to the source end of the first peaking pulse switch (Qp1).

  <First resonance part>

  The first resonating unit 320 includes the coil L1 and is applied with energy from the first energy storage unit 310 before the sustain voltage Vs is applied to the scan electrodes of the panel, and is greater than the sustain voltage Vs. A peaking pulse is formed by LC resonance and applied to the scan electrode.

  <First sustain voltage controller>

  The first sustain voltage controller 325 includes a first switch (Q1) that applies a sustain voltage (Vs) to the scan electrode and a second switch (Q2) that discharges the charge applied to the scan electrode at the ground.

  <Second energy storage unit>

  The second energy storage unit 330 includes a capacitor Cs2 that stores energy required to apply a peaking pulse higher than the sustain voltage Vs to the sustain electrode.

  <Second peaking pulse application section>

  The second peaking pulse applying unit 335 is connected in parallel to the second switch (Qp2) that is turned on when the energy supplied from the second energy storage unit 330 is supplied to the panel, and the second switch (Qp2). And a second diode D2 for injecting energy into the energy storage unit 330.

  At this time, the second peaking pulse switch (Qp2) is a MOS FET, the gate end of the MOS FET accepts an input of a timing signal, and the drain end of the MOS FET is connected to the second energy storage unit 330. The cathode end of the second diode (D2) is connected to the drain end of the switch (Qp2), and the anode end of the second diode (D2) is connected to the source end of the second peaking pulse switch (Qp2).

  <Second resonance part>

  The second resonating unit 340 includes the coil L2 and uses the energy supplied from the second energy storage unit 330 before the sustain voltage Vs is applied to the sustain electrode of the panel. ) A larger peaking pulse is formed by LC resonance and applied to the sustain electrode.

  <Second sustain voltage controller>

  The second sustain voltage controller 345 includes a third switch (Q3) for applying a sustain voltage (Vs) to the sustain electrode and a fourth switch (Q4) for discharging the charge applied to the Z electrode at the ground.

  If the waveform of the sustain pulse generated by the operation of the sustain driving circuit having such a structure is seen, as shown in FIG. 8, first, if the first peaking pulse switch (Qp1) is turned on, the first energy storage is performed. The energy stored in the capacitor (Cs1) of the unit 310 is injected into the panel (Cp) through the first peaking pulse applying unit 315, the coil (L1) of the first resonance unit 320, and the scan (Y) electrode. The peaking pulse larger than the sustain voltage is applied to the scan (Y) electrode by LC resonance.

  Next, when the peaking voltage reaches the maximum value, the first switch (Q1) and the fourth switch (Q4) are turned on, and the first peaking pulse switch (Qp1) is turned off. Accordingly, the sustain voltage (Vs) is applied to the scan (Y) electrode, and at the same time, the capacitor (Cs1) is charged through the first diode (D1), and the ground level is applied to the sustain (Z) electrode.

  In this process, two sustain discharges occur. That is, a sustain discharge occurs when a peaking pulse is applied, and a sustain discharge occurs again when a sustain voltage is applied to the scan (Y) electrode.

  As described above, the energy stored in the first energy storage unit 310 is injected into the panel (Cp), and the peaking pulse formed in the LC resonance is applied to increase the energy efficiency as compared with the conventional driving method. At the same time, the brightness is increased.

  Next, when the second peaking pulse switching (Qp2) is turned on, the energy stored in the capacitor (Cs2) of the second energy storage unit 330 is converted into the second peaking pulse application unit 335 and the second resonance unit 340. The peaking pulse larger than the sustain voltage is applied to the sustain (Z) electrode by LC resonance while being injected into the panel (Cp) through the coil (L2) and the sustain (Z) electrode.

  Next, when the peaking voltage reaches the maximum value, the third switch (Q3) and the second switch (Q2) are turned on, and the second peaking pulse switch (Qp2) is turned off. Accordingly, the sustain voltage (Vs) is applied to the sustain (Z) electrode, and at the same time, the capacitor (Cs2) is charged through the second diode (D2) to apply the ground level to the scan (Y) electrode.

  Even in this process, two sustain discharges occur. That is, a sustain discharge occurs when a peaking pulse is applied, and a sustain discharge occurs again when a sustain voltage is applied to the sustain (Z) electrode.

  As described above, the energy stored in the second energy storage unit 330 is injected into the panel (Cp) and the peaking pulse formed in the LC resonance is applied, so that the energy efficiency is higher than that of the conventional driving method. However, the brightness is increased.

  Meanwhile, the structure of the plasma display apparatus according to the second embodiment of the present invention is as shown in FIG.

  FIG. 9 is a view illustrating a structure of a second plasma display apparatus according to the present invention. As shown in the figure, the second plasma display apparatus according to the present invention includes a plasma display panel 100, a controller unit 110, a load measuring unit 120, a sustain pulse adjusting unit 130, a voltage adjusting unit 140, a scan driving unit 123, and a sustain driving unit. 124.

  <Controller section>

  The controller unit 110 converts the input video signal so as to be adapted to the plasma display panel, forms video data rearranged for each subfield, and assigns the number of sustain pulses for each subfield.

  <Load measurement section>

  The load measuring unit 120 receives video data rearranged for each subfield from the controller unit 110 and measures a load amount proportional to the number of cells turned on in one frame or one subfield. Then, the measured load amount is compared with the reference load amount, and if the measured load amount is larger than the reference load amount, a sustain pulse adjustment signal and a sustain voltage adjustment signal are output.

  <Sustain pulse adjustment unit>

  If the sustain pulse adjustment signal is not input from the load measurement unit 120, the sustain pulse adjustment unit 130 applies the sustain pulse signal having the number assigned by the controller unit 110 to the scan driving unit 123 and the sustain driving unit 124. When the sustain pulse adjustment signal is input from the load measurement unit 120, the sustain pulse adjustment unit 130 readjusts the number of sustain pulses and converts the number of sustain pulses to the scan drive unit 123 and the sustain drive unit 124. And apply to.

  <Voltage adjustment section>

  When the voltage adjustment unit 140 receives the sustain voltage adjustment signal from the load measurement unit 120, the voltage adjustment unit 140 determines an increase value of the sustain voltage, and operates the scan (Y) electrode of the panel according to the operations of the scan driving unit 123 and the sustain driving unit 124. If the sum of the reference sustain voltage and the increase value of the sustain voltage is applied to the sustain (Z) electrode and no sustain voltage adjustment signal is input, the operation of the scan driver 123 and the sustain driver 124 causes the panel to operate. A reference sustain voltage is applied to the scan (Y) electrode and the sustain (Z) electrode.

  At this time, the voltage adjustment unit 140 includes a DC / DC converter, and determines the increase value of the sustain voltage according to the pulse width of the sustain voltage adjustment signal. That is, the increase value of the sustain voltage increases as the pulse width of the sustain voltage adjustment signal increases.

  The first driving method of the plasma display apparatus according to the second embodiment having such a structure is as shown in FIG. 10, FIG. 11, and FIG.

  FIG. 10 is a sustain driving circuit diagram included in the scan driving unit and the sustain driving unit for explaining the first driving method of the plasma display apparatus according to the second embodiment of the present invention. FIG. 11 shows driving waveforms generated by the sustain driving circuit included in the scan driving unit and the sustain driving unit of FIG. FIG. 12 shows another driving waveform generated by the sustain driving circuit included in the scan driving unit and the sustain driving unit of FIG.

  First, as shown in FIG. 9, the controller unit 110 converts the input video signal so as to be adapted to the plasma display panel, and applies the sustain pulse for each subfield to the video data rearranged for each subfield. Assign the number.

  The load measuring unit 120 receives the video data rearranged for each serve field from the controller unit 110, measures the load amount, and compares the measured load amount with the reference load amount.

  If it is determined that the load amount measured by the load measuring unit 120 is smaller than the reference load amount, the sustain pulse adjusting unit 130 determines that the number of sustain pulses for each subfield assigned by the controller unit 110 is the scan electrode (Y) and As shown in FIG. 11, the sustain voltage is applied to the sustain electrode (Z), and the reference sustain voltage (Vs) is applied to the scan electrode and the sustain electrode by the voltage adjusting unit 140.

  Referring to FIG. 10, since the sustain pulse is applied to the scan electrode (Y), the first switch (Q1) and the fourth switch (Q4) are turned on, and the third switch (Q3) and The second switch (Q2) is turned off. As a result, the reference sustain voltage (Vs) is applied to the scan electrode (Y), and the sustain electrode (Z) becomes the ground level.

  Further, since the sustain pulse is applied to the sustain electrode (Z), the third switching (Q3) and the second switching (Q2) are turned on, and the first switch (Q1) and the fourth switch (Q4) are turned off. The As a result, the reference sustain voltage (Vs) is applied to the sustain electrode (Z), and the scan (Y) electrode becomes the ground level.

  On the other hand, if it is determined that the load amount measured by the load measuring unit 120 shown in FIG. 9 is larger than the reference load amount, the sustain pulse adjusting signal and the sustain voltage adjusting signal are respectively sent to the sustain pulse adjusting unit 130 and the voltage adjusting unit 140. Output.

  The sustain pulse adjusting unit 130 receiving the sustain pulse adjustment signal readjusts the number of sustain pulses, and the adjusted number of sustain pulses is applied to the scan electrode (Y) and the sustain electrode (Z). As described above, the scan driver 123 and the sustain driver 124 are controlled.

  In addition, the voltage regulator 140 that has received the sustain voltage adjustment signal outputs a sustain voltage increase value corresponding to the sustain voltage adjustment signal. Accordingly, the sustain voltage applied to the scan electrode (Y) and the sustain electrode (Z) is the sum (Vs') of the reference sustain voltage (Vs) and the sustain voltage increase value as shown in FIG.

  Referring to FIG. 10, since the sustain pulse is applied to the scan electrode (Y), the first switch (Q1) and the fourth switch (Q4) are turned on, and the third switch (Q3) and The second switch (Q2) is turned off. As a result, the sum (Vs') of the reference sustain voltage and the increase value of the sustain voltage is applied to the scan electrode (Y), and the sustain electrode (Z) becomes the ground level.

  Further, since the sustain pulse is applied to the sustain electrode (Z), the third switching (Q3) and the second switching (Q2) are turned on, and the first switch (Q1) and the fourth switch (Q4) are turned off. The As a result, the sum (Vs') of the reference sustain voltage and the sustain voltage increase value is applied to the sustain electrode (Z), and the scan electrode (Y) becomes the ground level.

  The plasma display apparatus according to the second embodiment driven by the first driving method increases brightness and contrast by increasing the sustain voltage according to the load amount of the input video data.

  FIG. 13 is a sustain driving circuit diagram included in the scan driving unit and the sustain driving unit for explaining a second driving method of the plasma display apparatus according to the second embodiment of the present invention. FIG. 14 shows driving waveforms generated by the sustain driving circuit included in the scan driving unit and the sustain driving unit of FIG. FIG. 15 shows another driving waveform generated by the sustain driving circuit included in the scan electrode driving unit and the sustain electrode driving unit shown in FIG.

  First, as shown in FIG. 9, the controller 110 converts the input video signal so as to be adapted to the plasma display panel, and the number of sustain pulses for each subfield with respect to the video data rearranged for each subfield. Assign.

  The load measurement unit 120 receives the video data rearranged for each serve field from the controller unit 110, measures the load amount, and compares the measured load amount with the reference load amount.

  If it is determined that the load amount measured by the load measuring unit 120 is smaller than the reference load amount, the sustain pulse adjusting unit 130 determines that the number of sustain pulses for each subfield assigned by the controller unit 110 is the scan electrode (Y) and As shown in FIG. 14, the sustain voltage is applied to the sustain electrode (Z), and the reference voltage (Vs) is applied to the scan electrode and the sustain electrode by the voltage adjusting unit 140. At this time, the sustain pulse applied to the scan electrode (Y) and the sustain electrode (Z) includes a peaking pulse.

  Referring to FIG. 13, when the first peaking pulse switch (Qp1) is turned on, the energy stored in the capacitor (Cs1) of the first energy storage unit 310 is converted into the first peaking pulse application unit ( 315), the coil (L1), and the Y electrode are injected into the panel (Cp), and a peaking pulse larger than the sustain voltage is applied to the Y electrode by LC resonance.

  Next, when the peaking voltage reaches the maximum value, the first switch (Q1) and the fourth switch (Q4) are turned on, and the first peaking pulse switch (Qp1) is turned off. As a result, the sustain voltage (Vs) is applied to the scan electrode (Y), and the capacitor (Cs1) is charged through the first diode (D1) to apply the ground level to the sustain electrode (Z).

  In this process, two sustain discharges occur. That is, a sustain discharge occurs when a peaking pulse is applied, and another sustain discharge occurs when a sustain voltage is applied to the scan electrode (Y).

  In this way, energy stored in the first energy storage unit 310 is injected into the panel Cp and a peaking pulse formed by LC resonance is applied to increase energy efficiency and increase luminance. .

  Next, when the second peaking pulse switching (Qp2) is turned on, the energy stored in the capacitor (Cs2) of the second energy storage unit 330 is converted into the second peaking pulse application unit 335, the coil (L2), and the like. The peaking pulse larger than the sustain voltage is applied to the sustain electrode (Z) by LC resonance while being injected into the panel (Cp) through the Z electrode.

  Next, when the peaking voltage reaches the maximum value, the third switch (Q3) and the second switch (Q2) are turned on, and the second peaking pulse switch (Qp2) is turned off. As a result, the sustain voltage (Vs) is applied to the sustain electrode (Z), the capacitor (Cs2) is charged through the second diode (D2), and the ground level is applied to the scan electrode (Y).

  Even in this process, two sustain discharges occur. That is, a sustain discharge occurs when a peaking pulse is applied, and a sustain discharge occurs again when a sustain voltage is applied to the sustain electrode (Z).

  On the other hand, if it is determined in FIG. 9 that the load amount measured by the load measuring unit 120 is larger than the reference load amount, the sustain pulse adjusting signal and the sustain voltage adjusting signal are respectively sent to the sustain pulse adjusting unit 130 and the voltage adjusting unit 140. Output.

  The sustain pulse adjusting unit 130 receiving the sustain pulse adjustment signal readjusts the number of sustain pulses, and the adjusted number of sustain pulses is applied to the scan electrode (Y) and the sustain electrode (Z). As described above, the scan driver 123 and the sustain driver 124 are controlled.

  In addition, the voltage adjustment unit 140 that receives the input of the sustain voltage adjustment signal outputs an increase value of the sustain voltage corresponding to the sustain voltage adjustment signal. Therefore, the sustain voltage applied to the Y electrode and the Z electrode is the sum (Vs') of the reference sustain voltage (Vs) and the sustain voltage increase value as shown in FIG. At this time, the sustain pulse applied to the scan electrode (Y) and the sustain electrode (Z) includes a peaking pulse.

  Referring to FIG. 13, if the first peaking pulse switch (Qp1) is turned on, the energy stored in the capacitor (Cs1) of the first energy storage unit 310 is applied to the first peaking pulse. Peaking is greater than the sum (Vs ′) of the reference sustain voltage (Vs) and the sustain voltage increase value due to LC resonance while being injected into the panel (Cp) through the part 315, the coil (L1), and the scan electrode (Y). A pulse is applied to the scan electrode (Y).

  Next, when the peaking voltage reaches the maximum value, the first switch (Q1) and the fourth switch (Q4) are turned on, and the first peaking pulse switch (Qp1) is turned off. As a result, the sum (Vs ′) of the reference sustain voltage (Vs) and the sustain voltage increase value is applied to the scan electrode (Y), and the capacitor (Cs1) is charged through the first diode (D1). A ground level is applied to (Z).

  In this process, two sustain discharges occur. That is, a sustain discharge occurs when a peaking pulse is applied, and a sustain discharge occurs again when a sustain voltage is applied to the scan electrode (Y).

  The second plasma display apparatus driven by the second driving method not only increases the brightness and contrast by increasing the sustain voltage according to the load amount of the input video data, but also includes a picking pulse. Energy efficiency can be increased by supplying a sustain pulse to the electrode and the sustain electrode.

FIG. 1 is a perspective view showing a structure of a three-electrode AC surface discharge type PDP having a discharge cell structure arranged in a conventional matrix form. FIG. 2 is a diagram showing drive waveforms for explaining a conventional PDP drive method. FIG. 3 is a diagram showing a conventional general sustain drive circuit. FIG. 4 is a diagram showing a general sustain pulse waveform. FIG. 5 is a diagram illustrating a method for realizing image gradation of a conventional plasma display panel. FIG. 6 schematically illustrates a first plasma display apparatus according to the present invention. FIG. 7 is a diagram showing a sustain driving circuit included in the scan driving unit and the sustain driving unit of the present invention. FIG. 8 is a pulse waveform diagram generated by the operation of the sustain drive circuit of the present invention. FIG. 9 is a view showing a structure of a second plasma display device according to the present invention. FIG. 10 is a sustain driving circuit diagram included in the scan driving unit and the sustain driving unit for explaining the first driving method of the second plasma display apparatus according to the present invention. FIG. 11 is a diagram illustrating driving waveforms generated by a sustain driving circuit included in the scan driving unit and the sustain driving unit of FIG. 12 is a diagram illustrating another driving waveform generated by a sustain driving circuit included in the scan driving unit and the sustain driving unit of FIG. FIG. 13 is a sustain driving circuit diagram included in a scan driving unit and a sustain driving unit for explaining a second driving method of the second plasma display apparatus according to the present invention. FIG. 14 is a diagram illustrating driving waveforms generated by a sustain driving circuit included in the scan driving unit and the sustain driving unit of FIG. FIG. 15 is a diagram illustrating another drive waveform generated by the sustain drive circuit included in the scan electrode drive unit and the sustain electrode drive unit of FIG.

Claims (20)

A plasma display panel having predetermined electrodes;
A sustain driving circuit configured to include a picking pulse in the one sustain pulse so that a plurality of discharges are generated by the one sustain pulse when the sustain pulse is supplied to the predetermined electrode of the plasma display panel; A scan drive unit and a sustain drive unit,
A plasma display device comprising:   The plasma display apparatus of claim 1, wherein the predetermined electrode of the plasma display panel includes at least one of a scan electrode and a sustain electrode. The sustain drive circuit is
A peaking pulse application unit including a peaking pulse switch that is turned on when supplying energy of the energy storage unit to the plasma display panel; and a diode for injecting energy into the energy storage unit;
A resonance unit that forms a peaking pulse by LC resonance using the energy of the energy storage unit and applies the peaking pulse to a scan electrode or a sustain electrode;
A sustain voltage controller for applying a sustain voltage or a ground level to the scan electrode or the sustain electrode;
The plasma display device according to claim 2, comprising:   The plasma display apparatus as claimed in claim 1, wherein the peaking pulse is applied to the scan electrode or the sustain electrode before a sustain voltage is applied. The gate end of the peaking pulse switch receives a timing signal, the drain end is connected to the energy storage unit, and the source end is connected to the anode end of the diode,
4. The plasma display apparatus according to claim 3, wherein a diode end of the diode is connected to a drain end of the peaking pulse switch, and an end of the diode is connected to a source end of the peaking pulse switch.   The plasma display apparatus as claimed in claim 4, wherein a voltage of the peaking pulse is larger than the sustain voltage. The resonance part includes a coil,
The plasma display apparatus according to claim 3, wherein one end of the coil is connected to a source end of the peaking pulse switching element, and the other end is connected to the scan electrode or the sustain electrode. . A load measuring unit that measures a load amount of the video data converted in conformity with the plasma display panel, and outputs a voltage adjustment signal by comparing the measured load amount with a reference load amount;
A voltage adjusting unit that adjusts a sustain voltage according to a voltage adjustment signal output from the load measuring unit and applies the voltage to a scan electrode or a sustain electrode of the plasma display panel;
2. The plasma display device according to claim 1, further comprising:   The voltage adjustment unit may supply a voltage higher than the sustain reference voltage to a scan electrode or a sustain electrode of the plasma display panel when the measured load amount is larger than a reference load amount. The plasma display device described. When the measured load amount is larger than a reference load amount, the method further includes a sustain pulse adjustment unit that receives a sustain pulse adjustment signal from the load measurement unit and adjusts the number of already assigned sustain pulses,
The sustain pulse adjustment unit controls the scan driving unit and the sustain driving unit to apply a total voltage of the reference sustain voltage and the increase value of the sustain voltage when supplying a sustain pulse to the scan electrode or the sustain electrode. To
The plasma display device according to claim 8.   9. The plasma display according to claim 8, wherein the voltage adjusting unit applies the reference sustain voltage to the scan electrode or the sustain electrode when the measured load amount is smaller than a reference load amount. apparatus. The voltage regulator includes a DC / DC converter,
12. The plasma display apparatus according to claim 8, wherein the DC / DC converter determines an increase value of a sustain voltage according to a pulse width of a sustain voltage adjustment signal. Converting the input video signal so as to hit the plasma display panel and forming the rearranged video data for each sub-field;
Receiving the input of video data rearranged for each serve field from the controller unit and measuring the load amount;
Comparing the measured load amount with a reference load amount and outputting a voltage regulation signal;
Determining a sustain voltage corresponding to the sustain voltage adjustment signal and applying the determined sustain voltage to the scan electrode or the sustain electrode of the plasma display panel;
A method for driving a plasma display device, comprising:   The method as claimed in claim 13, wherein when the measured load amount is larger than the reference load amount, the number of sustain pulses already assigned is adjusted.   The method of claim 13, further comprising: applying the reference sustain voltage to the scan electrode or the sustain electrode when the measured load amount is smaller than the reference load amount. The step of applying a determined sustain voltage to the scan electrode or the sustain electrode is as follows:
A peaking pulse formed by LC resonance is applied to the scan electrode while energy stored in advance is injected;
After the peaking pulse is applied, a sustain voltage is applied to the scan electrode, and the sustain electrode is at a ground level;
A peaking pulse formed by LC resonance is applied to the sustain electrode while energy stored in advance is injected;
After the peaking pulse is applied, a sustain voltage is applied to the sustain electrode and the scan electrode is at a ground level; and
14. The method of driving a plasma display apparatus according to claim 13, further comprising:   The method of claim 16, wherein the sustain voltage is applied when the peaking pulse voltage reaches a maximum value.   The method of claim 16, wherein the peaking pulse voltage is higher than the sustain voltage. 19. The method of driving a plasma display device according to claim 16, wherein discharge is generated by the peaking pulse.   The method as claimed in claim 13, wherein in the step of applying the sustain voltage, a plurality of discharges are generated by one sustain pulse.

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